Tinytags Monitor Temperature and RH to Aid Grassland Regeneration

Tinytag data loggers monitor outdoor temperature and humidity to aid research into restoration and planting of UK Grasslands.

As part of a project to restore species-rich grasslands on ex-arable land, robust Tinytag data loggers record soil temperature and RH to help understand planting and growing conditions. The loggers provide patterns of temperature and humidity data to help optimise seed germination.

Restoration of species-rich grasslands, that are of high value
because of the diverse flora and fauna that they support, is part
of the UK's strategy to preserve its native biodiversity. The
NERC Centre for Ecology & Hydrology (CEH)
worked in a project to test new methods to restore such types of
grassland at sites where they have disappeared due to agricultural
intensification. Understanding what goes on at grass roots level
with regard to abiotic conditions such as temperature and
humidity is an important part of the process. 192 Tinytag data
loggers have been used for this purpose at the Pegsdon
Hills Nature Reserve in the Chilterns from the summer of
2008.

Intensive arable farming and intensified grassland management in
the UK have resulted in the loss and fragmentation of high quality,
species-rich grasslands. A small number of high yielding grasses
that are better adapted to the conditions of high fertility
generated by intensive agriculture arable farming, have displaced
wild flowers and herbaceous flowering plants (known as 'forbs'),
such as rock rose, milk-wort and wild thyme.

The NERC Centre for Ecology & Hydrology is
looking at better ways to establish such species-rich grasslands at
existing agriculturally improved restoration sites. Such sites
often experience seed regeneration difficulties, as many forb
species are quite rare these days and restricted to a few remaining
sites less affected by agricultural intensification, and thus
generally do not naturally colonise restoration sites. Typically
the sites are chalk grassland. A second focus of the project is to
establish management regimes to prevent high yielding 'scrub'
grasses out-competing wild flower species after they have been
introduced from seed or via pre-grown 'plug' plants.

The data loggers have been deployed 3 times a year, in spring,
summer and autumn, for one week at a time. The loggers have
monitored factors that are known to affect plant establishment.
Temperature and
humidity data has been recorded at surface level, and temperature also in top
10cm of the soil profile. These factors are important for at
least two reasons: first, the seeds of many species possess inbuilt
mechanisms to time germination in response to fluctuations in light
and moisture levels. Too little fluctuation indicates too much
overlying dense vegetation, cutting light and taking moisture,
which would prevent new establishment from seed.

Seed germination in these species therefore only takes place
when there is sufficient fluctuation, indicating favourable
conditions for establishment. Second, the tiny seedling stage of a
plant is the stage most vulnerable to extremes in abiotic factors
such moisture, and getting these factors right is of crucial
importance for successful re-introduction of rare forb species.

Dr Markus Wagner is a Grassland Ecologist and
team co-ordinator of the project. He comments: "The Tinytag data
loggers have proved reliable, sturdy and easy to use. They have
provided us with patterns of temperature and humidity data that we
can relate to what we already know about seed germination in these
conditions and that help us with the interpretation of the results
of our study. Optimising methods of re-introduction offers us a
better chance of maximising establishment from seed which is often
hard to come by due to a lack of suitable 'donor' sites that can be
used for seed harvesting".

The project, funded by DEFRA, will continue to
refine methods for restoring species-rich grassland, meeting the
Government's biodiversity strategy but perhaps, more importantly,
helping to preserve a countryside rich with flora and fauna.

The Centre for Ecology & Hydrology (CEH) is
the UK's centre of excellence for research in land and freshwater
environmental sciences. Their work encompasses a wide range of
environmental disciplines ranging from the smallest genes to whole
Earth systems.